Gas producing and smoke consuming firebox and down draft kiln



2 Shee ts-Sheet l A RNEY W. E. WARWOOD Filed June 12, 1956 d f H w N E V w m a h .5 7 w i a W T Jan. 11, 1938.

GAS PRODUCING AND SMOKE CONSUMING FIREBOX AND DOWN DRAFT KILN Patented Jan. 11, 193 8 William Edred Warwood, Toronto, Ontario,

Oanad Application June 12, 1936, Serial No. 84,803

1 Claim.

The invention relates to improvements in gas producing and smoke consuming fireboxes and down draft kilns, as described in the present specification and illustrated in the accompanying drawings which form a part of the same.

The invention consists essentially of the novel features of construction pointed out broadly and specifically in the claims for novelty following a description in detail of an acceptable form of the V invention. 7

The objects of the invention are to devise a down draft kiln having underground fiues and a firebox or fireboxes of the drop arch type of brick construction, allowing the minimum amount of brickwork which will avoid as far as possible the formation and harbouring of moisture; deflecting and distributing the gases in such a manner as to obtain the greatest useful effect therefrom and at the same time obviate as far as practicable unequal expansion and contraction of the walls without checking the draft; to construct a firebox in which the green coal is separated from the fire until the gases are released, and, in which the combustion principally takes place in the kiln resulting in an increased quantity of air being drawn through the fire which oxidizes or burns every combustible particle in the firebox, minimizing the waste in the ash, producing a hotter fire, decreasing the amount of fuel consumed and obviating heat losses in the form of smoke which consists of carbon, combustible and non-combustible gases, to furnish oxygen in the form of preheated air prior to delivery to Where combustion is desired through properly defined passages effecting greater emciency, adapted in its passage to cool the arch supportingwalls preventing sagging of the firebox arches; eliminating drop in temperature when firing and producing a more uniform temperature by having the fiame in the kiln, rather than in the firebox producing the maximum of service; to construct a kiln in which the products of combustion are distributed around the entire interior thereof thereby heating the whole' more uniformly and thoroughly before flowing into the fiues and thence to the stack, and in which the sides and bottom are maintained at a more equable temperature than would be the case in those now generally employed; and since the carbon in the smoke is totally consumed a clean, uniform evenly coloured ware of uniform hardness and standard is assured; minimizing waste and increasing the qualities of the ware; and generally to provide a kiln of unified construction representing the most modern, economical and efiicient means of baking brick; the erection of which may be accomplished by the ordinary layman, readily accessible for examinatiomrepairing and cleaning; providing maximum combustion, minimum fuel consumption, durable in construction and efiicient for the particular purposes set forth.

In the drawings, Figure 1 is a sectional plan View of the kiln showing the arrangement of the underground fiues and smoke passages.

Figure 2 is a side elevation showing the arrangement of the fireboxes, vertical stays and tie-rods.

Figure 3 is a cross-sectional view taken on the lines 33 of Figure 1, showing the arrangement of the fire-box arches and fiues.

Figure 4 is an end elevation showing the wicket and cross tie-rods.

Figure 5 is a sectional view taken on the lines 5-5 of'Figure 3 showing the method of jointing, and the location of the preheating air passages.

Figure 6 is a side elevational view showing the firebox fuel opening, preheated air passages, and window.

Like numerals of reference indicate corresponding parts in the various figures.

Referring to the drawings, the kiln in which the bricks or ware, after being moulded and dried, are baked or burned, consists of the large combustion chamber H which is itself built of brick formed by the side walls !2, end cross walls 53 and it and the arched shaped crown or top 55. The interior of the kiln is completely lined with firebrick l6, and is reinforced by the exterior vertical members or buck stays I? and the longitudinal reinforcing members is which are built into the brick work and are for the purpose of unifying construction thus preventing bulging of the side walls and sagging of the crown, and may be in the form of channel iron, railroad rail iron, or other members of suitable cross-section. The verticals are securely held in position by the longitudinal and cross tie rods H) which have the turnbuckles 2a installed therein for securely tightening the rods on completion of the brickwork. The gas chambers 2! are suitably spaced along the side walls l2 and may be of any number depending on the length of the kiln; and are of step arch construction, the arches being lined with special arched fireclay bricks 22, and have the coking tables 23 which are built up of fireclay bricks 24 on which the green coal is placed and remains until the gases are withdrawn passing off up the throat 25 of the gas chamber 2! into the kiln or combustion chamber II which is the main combustion chamber as previously outlined;

ing injury to the joints or kiln walls l2.

as new coal is added to the coking table by way of the fuel opening 26 the coke at the inner edge 27 of the coking table 23 is pushed off into the ash pit 28' where the remaining substances burn off, the waste or clinkers being removed by way of the cleaning opening 29 provided for that purpose.

The arches 2IA are stepped downwardly toward the rear of the coking table 23 which considerably decreases the area of the fuel opening 26 at this point. The coal on the coking table forms the door, and this cutting down of the fuel opening prevents back draft caused by baflling air currents, affording greater protection to the crown of the fuelingichamber and prevents the coal or coke from dropping down into the ash pit. The gas chamber side walls 30 and backwalls Si or bag-walls as they are known to the art are stepped back at 32 at a point above the fuel opening 26 which permits expansion and splitting of the gases and freer passage thereof into the kiln or combustion chamber l I where the main combustion takes place.

The gas chamber side walls 30 and the ash pit walls 33 are butted to the kiln walls l2 and permit expansion and contraction without caus- The preheated air passages 34 and 35 formed interiorly of the kiln walls 52 at the joint of the kiln walls i2 and the ash pit walls 33, have the cross inlet passages 36 and 3? leading from the exterior of the kiln walls l2 thereinto; the passages 34 and 35 pass upwardly along the outer faces of the arch 38 joining the upper cross passage 39 which opens into the kiln or combustion chamber at apoint directly over the top of the bagwalls 30--3I; the cool air which is drawn into the kiln enters into the air passages 34- and 35 through the openings til-4| and in its passage cools the outer surfaces of the arch supporting Walls, and in its accent is preheated Which considerably increases efiiciency. The air passage 39 has also the branch cross passage 42 leading outwardly to the exterior of the kiln which is covered by the hinged door 3 having the mica window M formed therein and is for the purpose of either supplying air directly into the interior of the kiln or for viewing the contacts or the condition of the interior.

The kiln has the doors or wickets 45 located in the end walls for entry into the interior for filling purposes and removing the ware on completion of baking, and has also the cooling openings 46 located in the end walls and crown, all of which are bricked in solidly during baking operations.

The kiln fioor 41 is composed of bricks placed on edge, half brick spacing, which rest on midfeathers or crosswalls 48 composed of bricks arranged in checker formation well known to the art, and has thereunder the well arranged series of fiues or passages 49 which lead into longitudinal centrally located passage or main flue 50, which has the connecting passages 5| connected thereto leading to the main smoke trunk 52 which leads to a suitably located smokestack (not shown). The layers of brick which form the kiln floor are so arranged that the heated air circulates thereinbetween before passing downwardly through suitably arranged openings 54 into fiues 49.

It is of course understood that the feature of providing preheated air to the gases emitted from the firebox to form the proper combustion entering the combustion chamber, can be equally adaptable to many kinds of furnaces, such as annealing furnaces, roasting furnaces, lime kilns, pottery kilns and in various forms of boilers.

In the operation of the invention, the ware which has been previously dried, is placed or set in the kiln in a pile or piles suitably arranged, and the wickets and cooling openings are solidly bricked in. The furnaces are lighted, coal being supplied by way of the mouths or feeding openings and the fire is gradually built up until it reaches the height of the coking tables.

When the fire has been built up to the level of the coking tables, the openings are completely filled with coal which remains on the tables until the gases are withdrawn. As new coal is added, the coke at the exterior end of the tables is pushed off into the ashpits where the remaining substances are consumed. The gases passing oil from the green coal pass off upwardly, meeting the preheated air being drawn into the interior through the air passages, splitting and flowing around the interior, entirely enveloping the ware before passing into the underground fiues and thence to the atmosphere.

What I claim is:

In gas producing and smoke consuming fire boxes and down draft kilns, a ln'ln comprising a combustion chamber having an arched crown and air passages leading through the crown por tion and through the side wall adjacent to the crown portion, a floor beneath the combustion chamber and having a series of fines leading to a common flue, a plurality of gas chambers par tially within said combustion chamber and having vertical discharge thereinto, feed inlets leading into said gas chambers, a plurality of coke tables within said gas chambers adapted to hold the fuel, ash outlets leading into said gas chambers, said gas chambers having arches adjacent to the fuel inlets in downward step formation and terminating in the vertical discharges.

WILLIAM EDRED WARWOOD. 

